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Date: Wed, 11 Aug 2004 22:19:55 -0500
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Message-ID: <200408112219.55268.dan@ostrowski.cc>
Subject: Re: [PHP-DEV] is_a() vs. instanceof
From: dan@ostrowski.cc (Dan Ostrowski)

On Tuesday 10 August 2004 7:36 pm, Hans Lellelid wrote:
> I like the new $obj instanceof ClassName way of checking class /
> interface types, .... but this method does have one major drawback
> compared to the old is_a() approach:
>
>     The class must be loaded in order to perform an instanceof check!
>

Isn't that the point? is_a() and instanceof are ways of checking the class of 
an object at runtime where it could be any number of things. ( And here I'm 
assuming you mean instantiated instead of "loaded"? )

If you don't have an instantiated object.. what do you have? A class! And THAT 
can be checked at "compile" ( or in this case write ) time. There's something 
wrong with my code, if I'm thinking of this right, if I have no idea if class 
A is a subclass of class B.

Now, if I'm passed random objects, I may want to know of which types they 
are... which is where these functions/builtins come in...

Am I misunderstanding you?


Dan Ostrowski